Anyone ever try to mix 'n' match GM factory parts to create a good air cleaner for our cars?
The idea is to get good flow, cold air, no interference, and also get rid of the lift ring....all in a stock-appearing package.

 

The only stock appearing intake would be the dual snorkel or a plain open element. Some people see the open element and think that you have a carb. Most other intake do not fit under our hood. If we had more room we could use the ones found on trucks and caprice cars.

 

I found something very likely to work:
Cadillac 4.1L TBI intake with the filter and lid from a Buick 3.8L 2 barrel.
It sits right, doesn't interfere, has a massive cold air intake potential and looks factory to the casual observer

We're gonna tackle it today and take pics.
-John

 

here's the air cleaner we're starting with, except the element and lid will be from a Buick 3.8L G-body with Dualjet carb. Filter's an additional inch taller and has no lettering on it.

This intake can be found at your local boneyard in mid '80s Sevilles.
I picked up the lid, filter, base, heat stove tube (won't be used, just there for decoration) and wingnut all for $10.

 

And here's the lid. It can be found on mid '80s 3.8L Regals (not turbo)..

 

Some numbers affecting flow:
the narrowest part of the airhorn is 6"x1 1/2", or 9 square inches. Same as a circular tube 3 1/2" in diameter. We're gonna open it up some
The filter element is 3 1/2"x 10", 110 in^2. Same area as a 14x 2 1/2.
Calculated drop for a paper filter is less than .5 in/Hg (assuming a 305 revving out to 6k RPM). Should be plenty of filter.

 

A 3.5" piece of tubing has more inlet area than the 6"x1.5" by roughly 6/10". It is close though. The point is that will be your limiting factor for air flow. It doesn't matter how big your element is if you are going to choke it off. A 14x3 element has 132 in^2 of surface area. Every bit of that is exposed whereas a snorkel reduces that. I am all for a cold air kit for our cars and the best one I have seen to this day is the moddified TPI set-up.

 

Shifty,
True, but that's not the point...
Yes an open element 14x3 will out-flow this. Will it make more power? Definitely on a race car. On a street car? maybe a few. Then again, the density increase from cool air is a good equalizer, so maybe not.
Point is a big ol' chrome air cleaner with K&N element is obvious.
People see that and go "wow, that engine must be hopped up".
Now s'posin' you do some sneaky stuff, start out running some decent (not great, but decent) street hardware in your little TBI 305. You pop the hood and show 'em....nuthin'.
That's the point of the whole thing.
-John

(edit) and the entire filter is exposed to airflow. I agree that necking it down creates a restriction. That's why we're gonna open it up some. (end edit)

 

The first part of the installation is done. I still gotta get the pics developed and scanned. Took us about 20 minutes.
Still gotta plug the openings for the oil breather and heat riser and I haven't plumbed cold air to it yet.
I can't perceive any difference from the open air filter I had on previously. Still patches into second (bone stock L03). I'm callin' it good.

 

Oh ok I see now. Yea that would be a cool idea I geuss. You will have to show us the final product. I thougth you were trying to create something that was better than an open element yet look just like stock.

 

The caddy aircleaner would be great for our 327! i once had a crazy idea on a cold air open elment where i kept the stock inlet and cut a nice few hole in the back on the cleaner. it would be quite sleeper cuase noone looks or cares about our stock intake. but thats a dumb idea cuase all kids of stuf would get past the filter and plus its easyer jsut to buy an open element. oh and shifty i think i asked you in my other thred but do you think the 327 with a extreme lid would clear the stock hood or will i need to go out and buy a nice 2 1/4' or 3' cowl?

 

Yea I answered that. You may want to go back and read that.

 

thank what about the free cowl mod you can do to these cars with an extreme lid do you think that will do much?

 

It won't do much. Even with the hood insulation removed and the rear hood seal taken out, the hood is still right up against it. You are already getting enough air through the sides of the TBI unit. PLus the desing of the TBI unit has a hard time pulling air over the inejctors. Because of that you will see that 99% of the intake charge is mixed with air that has been drawn in from the sides.

 

Okay, got some pics uploaded.

First major problem with the stock air cleaner is that ridiculous little air horn. Although the hole at the end is reasonable it necks down to a tiny 1 1/2"x 2" straw. In comparison....


Next problem is the spacer ring and diverter ring combo on the stock cleaner, which really obstructs airflow into the throttle body.
In comparison...


Final problem is the air filter, which is a little small. I don't have a pic of the stock one, which measures 12"x2 1/2" for a total surface area of 94 in2. The new one is 10"x 3 1/2", or 110 in2. This is still a little smaller than I'd like, but good for a 305 winding out to 6500.


I wanted it to look stock, so here goes. Notice from the sides that the air cleaner leans forward at just the right angle (it was designed that way) to clear the hood. Also no threat of interference with the ignition.
Front

driver's side

pass side


Here's the rest of the images. I still have to develop and scan the pics we took doing the mods.
before

and after

 

well crap....pics no worky
okay, I'll try to upload 'em direct
#1 throat comparison

 

pic#2 throttle body comparison

 

pic #3 air filter

 

pic 4 front view

 

pic 5 driver's side

 

pic 6 passenger side

 

pic 7 before

 

pic 8 after

 

Ya know, these pics really bring home just how restrictive the stock air cleaner is.
*Air horn: 2"x1 1/2"
*Lift ring: forces all the air to flow vertically past the injector tower.
*Filter: 94 square inches (a little undersized)
There's also these...
*Drop base: Blocks flow to the bottom half of the filter rendering it useless. The filter behaves as if it's even smaller.
* That goofy ring directly above the injectors. Obstructs flow both by acting like another spacer and also it's proximity to the closed lid.
What a crappy design!!

 

Those pics really do show an improvement. That assemlby does not shroud the TBI inlet as much as the stocker does. You have posted more than the 3 pic limit but I will let it stand for now so that people may consider this as an alternative to an open element. Esspecially those who have visual inspection.

 

shifty,
Sorry about that...I tried to host 'em elsewhere

 

Don't worry about it. This can be vary usefull for people who want a little more performance but can't get away with an open element.

 

What is that air cleaner assy off of ?

Steve

 

Steve,
Base is from an '85 Cadillac Seville. Lid and filter are from an '86 Buick Regal 3.8 without the turbo.
-John

 

thats a good idea, I'll have to check the junkyards this spring

 

Are you planning on ducting cold air to it or just leaving it the way it is?

Steve

 

I'm planning on opening the air horn a little bit and ducting cold air to it.
-John

 

I hadn't seen this one before. I like it. It would be fun to get a second snorkle and weld it to the base on the other side of the engine. Then duct both to cold air via the usual methods.

Then add genuine GM decal to the air cleaner lid.

 

I just noticed that you have a stock hood, how bad does the air cleaner top hit it if any?

Steve

 

This looks pretty stock for a chevy IMHO, but maybe not for a Camaro, depending on the year. This is my 78 Caprice, but I did it on my 89 Caprice w/ TBI too, so it can def work for you guys. I basically cut up a second intake and tacked a second snorkle on.

You can check out the whole write up on my page:
http://home.earthlink.net/~guy1139/bigcoupe.htm

 

Very cool stuff here! I need one of these because I am tired of the *******-style air cleaner I have now. The idea of tacking another snorkel to it is a grand idea. Looks like I'm going junkyard jumping today.

 

Here is one you can plumb thru the FW to cold air then add a snotkel from there.
Look for the caprice.

 

That's pretty cool...too bad there wasn't a single one of those in the junkyard I went to the other day.

 

That thing is pretty cool. One question, is it clearenced in the rear of the cleaner for the dist? I cant use anything but a little 10x2 air cleaner because of the dist being right behind the tbi. REally sucks in hot weather to only be able to get hot *** air off the headers.

 

If you can weld, you can make something that will work. I think that is the whole idea behind the above pics. Maybe you could take an OEM air cleaner and cut it out for another redirected intake horn. Weld it into place with a MIG and voila! Instant air cleaner.

 

check out this post... very nice setup using modified factory produced parts

https://www.thirdgen.org/techbb2/sho...ht=air+cleaner

 

That is cool! I am wondering what it would do to your BLMs, though. Would you have to do any tuning after the installation?

 

i was at the pull a part this weekend and saw several of these air cleaners. they're really small. while the internal restriction around the throttle body is obviously much improved, this is a really small air cleaner. the opening at the air intake is tiny and not much larger than the stock one. i don't think there's a lot of improvement here.

 

I'm gonna add this thread into my Open Element sticky at the top. This definetly has some good info in it...



Bruce (90RS305)

 

I'm just a little bored and thought I might toss in my two cents.

I have a 1987 Caprice Classic 4BBL. I bought it for six hundred dollars to drive in the winter, because the salt here really rots cars. Anyhow, for no other good reason than for the sound, I went with a bit of a backyard open element. I took the lid off the air cleaner, brushed off the crud, flipped it upside down and twisted the hell out of the wing nut. It still sealed along the top of the air filter as well as leaving the majority of it exposed to the air. Of course, I don't think it did anything for perfomance at all (which I wasn't interested in anyway) in fact, it problably hurt perfomance, instead of getting nice cool air by the grill, it had to suck in all the hot air around the engine. It sure did make a neat sound when the four barrel kicked in, though.